Process for producing products from artificial silk



Patented July 7, 1936 PATENT OFFICE PROCESS FOR PRODUCING PRODUCTS FROM ARTIFICIAL SILK Georges Heberlein,

Wattwil,

Switzerland, as-

signor to Heberlein Patent Corporation, New York, N. Y., a corporation of New York No Drawing. Application April 4,1932, Serial No. 603,219. In Germany April 9,1931

2 Claims. (Cl. 18--54) This invention relates to novel materials from artificial silk, and particularly materials in the form of stiff filaments having a stiffness like straw or horsehair and suitable for use as substitutes for straw and horsehair and for other purposes. The invention also relates to the process for making these materials.v

In the copending application; Ser. No. 161,02 filed January 13, 1927, there is described the action of various swelling agents upon artificial silk threads except acetate silk. By the action of the swelling agents described upon such threads where the time of action is short or the other conditions including the concentration and tempera- 5 ture are of a regulated predetermined severity,

the fibers are first caused to undergo a superficial swelling and coagulate after washing out of the swelling agent whereby certain alterations occur therein, such as reduction in luster, in-

crease in translucency, etc. According to the present invention, however, a different type of material is produced and one which under the conditions set forth in my copending application 161,022 would not be produced.

5 The invention accordingly comprises the novel devices and combinations thereof together with the novel processes and steps of processes to be employed with such devices and combinations, specific embodiments of which are described here- 30 inafter by way of example and in accordance with which I now prefer to practice the invention;

According to the present invention the swelling action is produced in a stronger manner in such a way that the fibers, at least those located ex- 35 ternally upon the surface of the thread, are

caused to swell so strongly that, after coagulation, they will appear firmly and inseparably welded or melted together into a new structure. An important characteristic of the novel struc- 40 tures thus obtained is the cross-section which shows that at least the constituent fibrils located peripherally are no longer distinguishable as such, but have been welded together or consolidated into a homogeneous or cohesive mass en- 45 closing or enveloping like a rind, as it were, such elementary fibrils as are located interiorly.

If the swelling action is continued or pushed very far, then also the interior fibrils may be welded together. By exerting a certain longi- 50 tudinal pull (Langszuges) during the swelling and coagulating process, the agglutination of the fibrils will be promoted additionally.

These new stiff fibrous structures evidence externally a certain resemblance to the filamentary 55 material found on the market under the name of artificial horsehair, though they differ essentially therefrom since they do not possess the same glass-like, brittle character which is the chief property of the said known material. According tothe nature and the mode of application of the 5 swelling agents it is possible to obtain products of different stifiness. The lustre of the new fibrous structure of this invention may range all the way from high silky lustre to absolutely lustreless effects. The ensuing products exhibit the 10 properties of certain kinds of straw used in the braiding and interweaving industries.

For use as swelling means I may employ those customary for cellulose, for instance, alkali hydroxides, sulfuric acid, phosphoric acid, hydrol5 chloric acid, nitric acid, or mixturesof the said acids, concentrated solutions of zinc and rhodan (sulfo-cyanide) salts and ammoniacal copper oxide. The concentration and the time of action may vary within wide limits, according to the 20 property of. the starting material and the final effect to be secured. When using acid as the swellingagent, recourse may conveniently be had to anti-degradation addition materials known in the prior art, such as alcohols, heterocyclic bases and formaldehyde. .According to'the kind and nature of the swelling agent it is possible to work at different temperature, the temperature being more or less reduced preferably whenever acids are employed, while rather an increase of temperature is chosen in the case of salts.

All kinds of threads of artificial silk which are made up of a plurality of single fibres, including the so-called staple fiber yarns, are suited to be employed as starting materials, both threads made of cellulose hydrate as well as cellulose esters. As a general rule artificial threads or filaments of higher titres (titers) are especially suited for the new process, without, however, any

limitation being imposed in this respect, for if the treatment is applied with suflicient care, also finer artificial filaments are workable. It is advantageous also to use as a starting material'two or more ply thread or yarns of homogeneous or mixed artificial fibrous material. The amount or the nature of the twist, both of simple threads as well as of yarns, has an influence upon the finished product, most particularly the lustre, the latter as a result being thus widely variable. The new process is adapted also to mixed threads or yarns consisting of artificial fibers and vegetable fibers. In case the constituents of mixed yarns of different composition exhibit dissimilar behaviour when swelled, then the finished product often evidences a curly appearance. The new artificial materials which are dyed in the usual way prior to or after the swelling treatment, may be employed as a substitute for horsehair and as a braiding material. In the case of mixed yarns exhibiting different properties from the dyeing viewpoint, the new process is capable of producing'peculiar color effects; by preliminary and after-dyeing.

Examples 1. A thread consisting of 5-ply cupramonium silk yarn of 120 Den. is passed through a vat containing caustic soda of 20 B., the time of action being set at 20 seconds, at room temperature, whereupon the thread is thoroughly washed immediately and neutralized; After drying there results a stiff, silver-lustrous filament presenting a closed outer surface, in which the outer fibers are welded together. of the product obtained, especially when dyed, is like certainv qualities of straw.

2. Mixed yarn comprising a filament of mercerized cotton yarn 50/2 and a thread of cuprammonium silk 120 Den. is exposed for8 seconds to the action of sulfuric acid of 54,5" B. at +5 C. followed immediately by washing. It is then treated according to Example 1. The dry new structure represents a stifi light bodied curled dull thread, looking very much like horsehair frilled through twisting.

3. Upon a viscose filament of 300 Den. is brought to act sulfuric acid of 52,3 B. with an addition of 3% formaldehyde for 6 seconds at room temperature. The washed and dried filament has the stiffness of horsehair and is feebly translucent, presenting a smooth surface with a slight lustre.

4. An acetate silk (or acetyl cellulose silk) thread of 100 Den. five-ply, is subjected for 20 seconds to the action of calcium sulfo-cyanide solution of 25 B. at room temperature, and is then washed. What thus results is a thread having a property similar to that in Example 1, though the properties of acetate silk in the dyeing respect are perfectly preserved.

5. Viscose twist 500 Den. is drained during 20 seconds through a bath with a. zinc-chloride so- The character lution of 690 B. (measured at +15 C.) heated up to 80 C., and washed immediately afterwards. When dried, a stiff twist, in character similar to Example 3, is obtained.

6. Subject a viscose thread of 400 Den. to nitric acid of 45,5 B., during 10 seconds, at room temperature. After washing, the yarn is dried under slight stretching. In the finished state, the product shows a strawlike character, as described in Example 1.

Having thus described my invention with particularity with reference to the preferred methods of carrying out the same, it will be obvious to those skilled in the. art, after understanding my invention, that various changes and modifications maybe made therein without departing from-the spirit and scope of my invention, and I aim in. the appended claims to cover such changes and modifications as are within the scope of the invention.

What. is: claimed as new and desired to be secured by Letters Patent, is:'--

1'. A method of the kind described which com prisessubjecting a mixture of artificial silk and cotton in dried form to aswelling agent capable of affecting the artificial silk and cotton differently, said agent causing stiffening of the artificial silk and being capable of modifying permanently the character such as the texture or appearance of said artificial silk, and welding the artificial silk and cotton together and drying the same to produce a stiffened consolidated filament having a dull lustre and being crinkly and lightbodied in character.

2. A method for producing a novel stifi material' which comprises twisting an artificial silk thread and another thread, each in dried form, capable of swelling unequally when the combined thread is subjected to a swelling agent for stiffening the artificial thread, bringing the combined threads into contact with the swelling agent to cause unequal swelling and drying the same to produce a stifi crimped filament like horsehair.

GEORGES HEBERLEIN.

Certificate of Correction Patent No. 2,046,741 Ju1 7, 1936.

GEORGES HEBERLEIN It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 2, second column, line 1,

Example 5, for the numeral 690 read 69; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 1st day of September, A. D. 1936.

[SEAL] LESLIE FRAZER, Acting Commissioner of Patents. 

